Patent Application
20210188519
The disclosed concept relates generally to methods for packaging and preserving crustaceans, such as shrimp and crabs. More particularly, the disclosed concept relates to use of packaging for comestible crustacean material, preferably for fresh crustaceans (including thawed after freezing), in ambient environments without applying modified atmosphere packaging methods or a vacuum within the package. Packaging according to the disclosed concept has been found to improve shelf life of such products.
Standard bulk packaging for fresh crustaceans is typically achieved using metal or plastic cans, trays or tubs. Crustaceans exude liquid, which tends to pool in the bottom of conventional crustacean packaging. In this manner, crustaceans in a conventional package will often sit within their own exudate, which causes the food to quickly degrade. Fresh crustaceans packaged in this manner and stored above freezing typically do not last more than a few days. Even then, the seafood is often discolored and presents an unpleasant odor.
Short shelf life is a big problem in the seafood market because by the time fresh seafood reaches the shelves for wholesale or retail purchase, it has typically already lost a good portion of its useful life between catching, packaging, warehousing and shipping. Accordingly, there is a strong need for improved packaging for comestible crustacean material, which extends the shelf life.
Accordingly, in one optional embodiment, a method of packaging and preserving comestible crustacean material is provided. The method includes placing comestible crustacean material in a product containing space of a storage container atop a platform of a support structure. The storage container includes an internal compartment having the product containing space, the support structure defining the platform for supporting the comestible crustacean material. The internal compartment further includes a reservoir below the platform. The reservoir is configured to retain liquid. The platform and/or support structure are configured to direct liquid exuded from the comestible crustacean material to the reservoir.
In another optional embodiment, a method of packaging and preserving comestible crustacean material is provided. The method includes providing a storage container that defines an internal compartment. The internal compartment includes a reservoir and a product containing space above the reservoir. The storage container includes a base and a sidewall extending upwardly from the base, the base and at least a portion of the sidewall extending therefrom defining the reservoir. The reservoir is configured to retain liquid. A support structure is disposed within the internal compartment, the support structure defining a platform located above the reservoir. The support structure and/or platform include one or more of: a liquid permeable surface; one or more openings; and a ramp providing for liquid runoff from a side of the platform. The one or more of the liquid permeable surface, the one or more openings and the ramp, are configured to direct liquid exuded from the comestible crustacean material into the reservoir. The method further includes placing the comestible crustacean material in the storage container atop the platform.
Optionally, in any embodiment, the storage container is formed from a thermoformed polymer tray. Optionally, in any embodiment, the storage container is formed from a material other than a polymer.
Optionally, in any embodiment, an absorbent material is provided in the reservoir.
Optionally, the absorbent material includes a gel-forming polymer.
Optionally, in any embodiment, the reservoir is devoid of an absorbent material.
Optionally, in any embodiment, a lid encloses the comestible crustacean material within the product containing space. Optionally, the lid is a lidding film which is preferably oxygen permeable.
Optionally, in any embodiment, empty space surrounding and/or above the comestible crustacean material, beneath the lid and within the product containing space, forms a headspace. Thus, a headspace is formed within a volume of the product containing space and beneath the lid that is not occupied by the comestible crustacean material. In such a configuration, neither a lid nor another cover would be tightly wrapped directly onto or around the product. If a cover or film were to be tightly wrapped directly onto or around the product, then the product containing space would lack a headspace.
Optionally, in any embodiment in which an absorbent material is used, the comestible crustacean material is positioned above the absorbent material but is not in direct physical contact with the absorbent material.
Optionally, in any embodiment, the product containing space is not hermetically sealed.
Optionally, in any embodiment, the product containing space has the same pressure as the ambient environment surrounding the container.
Optionally, in any embodiment, the container allows for oxygen exchange and air exchange into and out of the container, i.e., bidirectionally. Preferably, it is the lid or lidding film that allows for oxygen exchange and air exchange into and out of the container.
The invention will be described in conjunction with the following drawings in which like reference numerals designate like elements and wherein:
While systems, devices and methods are described herein by way of examples and embodiments, those skilled in the art recognize that the presently disclosed technology is not limited to the embodiments or drawings described. Rather, the presently disclosed technology covers all modifications, equivalents and alternatives falling within the spirit and scope of the appended claims. Features of any one embodiment disclosed herein can be omitted or incorporated into another embodiment.
Any headings used herein are for organizational purposes only and are not meant to limit the scope of the description or the claims. As used herein, the word “may” is used in a permissive sense (i.e., meaning having the potential to) rather than the mandatory sense (i.e., meaning must). Unless specifically set forth herein, the terms “a,” “an” and “the” are not limited to one element but instead should be read as meaning “at least one.”
As used in this disclosure, the term “comestible crustacean material” refers to crustacean seafood that is fit for consumption, e.g., after preparation such as by cooking. The term “comestible crustacean material” can refer to edible portions of the crustacean as well as nonedible portions of the crustacean that are packaged with the edible portions, in a storage container. For example, crustaceans are often packaged within their exoskeletons. While the exoskeletons would not themselves be considered edible, they are encompassed within the phrase “comestible crustacean material” because they are provided as part of the crustacean material as packaged in the storage container.
As used in this disclosure, the term “fresh,” e.g., as in “fresh comestible crustacean material,” refers to seafood that is stored in temperatures above freezing, whether the seafood is dead or living. Previously frozen seafood may be considered “fresh” once it is stored above freezing.
As used in this disclosure, the term “platform” generally refers to a bed or floor atop which comestible crustacean material can be placed for storage. The term “platform” may optionally include a single, continuous supporting surface. For example, the platform may include a tabletop-like solid surface, a slanted roof-like solid surface or a convex-shaped solid surface. In another example of a single, continuous supporting surface embodiment of a platform, a substantially flat filter or membrane (such as a non-woven material) may be provided. Alternatively, the platform may optionally include a surface comprising small openings akin to a food strainer, a mesh or a screen. Alternatively, the term “platform” as used herein may refer to a plurality of separate supporting surfaces that cumulatively provide a bed or floor atop which comestible crustacean material can be placed for storage, according to an optional aspect of the disclosed concept. In optional embodiments, the platform may include a food contacting surface (e.g., of a filter), a filter or membrane and a supporting surface (e.g., upper surface of a rib or mesh screen) directly beneath it. Optionally, the platform is integral with the remainder of the storage container. Alternatively, the platform is or comprises a separate component that is assembled with or removably disposed within the remainder of the storage container.
Referring now in detail to the various figures of the drawings wherein like reference numerals refer to like parts, there are shown in
In one aspect of the disclosed concept, a storage container 10, 110, 210, 310, 410, 510, 610 is provided. The storage container 10, 110, 210, 310, 410, 510, 610 comprises an internal compartment 12, 112, 212, 312, 412, 512, 612 having a product containing space 14, 114, 214, 314, 414, 514, 614 for holding comestible crustacean material 16 and a reservoir 18, 118, 218, 318, 418, 518, 618 below the product containing space 14, 114, 214, 314, 414, 514, 614. The reservoir 18, 118, 218, 318, 418, 518, 618 is configured to retain liquid exudate from the comestible crustacean material 16.
As depicted in the figures, the comestible crustacean material 16 comprises live oysters in their shells. This is merely representative and not limiting, with respect to the types of comestible crustacean material that may be stored in any embodiment of the storage containers 10, 110, 210, 310, 410, 510, 610. Optionally, in any embodiment, the comestible crustacean material may include one or more of the following species: crabs, lobsters, shrimp, crawfish, prawns and hill. The foregoing list is illustrative and not exhaustive; other comestible crustacean material may be used according to aspects of the disclosed concept. In some cases, the comestible crustacean material may be provided whole, in their exoskeletons. In other cases, parts of the comestible crustacean material may be provided or the meat alone (removed from the exoskeleton) may be provided, according to optional aspects of the disclosed concept.
It is preferred, albeit optional, that an absorbent material 20 is provided within the reservoir 18, 118, 218, 318, 418, 518, 618. In any embodiment, the absorbent material may be in the form of one or more of: absorbent powders, granules, fibers, a sponge, a gel and a coating on a surface within the reservoir, for example. A preferred absorbent material includes solid powder or granules that form a gel upon absorbing liquid. In this manner, when liquid exuded from the comestible crustacean material 16 flows or drips into the reservoir 18, 118, 218, 318, 418, 518, 618, the absorbent material 20 absorbs the liquid (e.g., by becoming gelatinous) so as to prevent the liquid from splashing, flowing or leaking from the reservoir 18, 118, 218, 318, 418, 518, 618 back into the product containing space 14, 114, 214, 314, 414, 514, 614. Optional absorbent materials for use in any embodiment of the disclosed concept are further elaborated upon below.
The storage container 10, 110, 210, 310, 410, 510, 610 optionally comprises a base 22, 122, 222, 322, 422, 522, 622 and a sidewall 24, 124, 224, 324, 424, 524, 624 extending upwardly from the base 22, 122, 222, 322, 422, 522, 622. The base 22, 122, 222, 322, 422, 522, 622 and at least a portion of the sidewall 24, 124, 224, 324, 424, 524, 624 (e.g., a portion directly and continuously extending from the base 22, 122, 222, 322, 422, 522, 622) define the reservoir 18, 118, 218, 318, 418, 518, 618. The reservoir 18, 118, 218, 318, 418, 518, 618 is preferably fully enclosed along the base 22, 122, 222, 322, 422, 522, 622 and along at least a portion of the sidewall 24, 124, 224, 324, 424, 524, 624 extending directly and continuously from the base 22, 122, 222, 322, 422, 522, 622. In this manner, for example, the reservoir 18, 118, 218, 318, 418, 518, 618 is configured to retain liquid, such as liquid exudate from seafood packaged in the storage container 10, 110, 210, 310, 410, 510, 610. Accordingly, the reservoir 18, 118, 218, 318, 418, 518, 618 is configured to prevent liquid received therein from leaking outside of the storage container 10, 110, 210, 310, 410, 510, 610. Optionally, the sidewall 24, 124, 224, 324, 424, 624 terminates at a peripheral edge 26, 126, 226, 326, 426, 626 surrounding a container opening 28, 128, 228, 328, 428, 628 through which comestible crustacean material may be deposited into the storage container 10, 110, 210, 310, 410, 610 or removed therefrom.
The storage container 10, 110, 210, 310, 410, 510, 610 further comprises a support structure 30, 130, 230, 330, 430, 530, 630 disposed in the internal compartment 12, 112, 212, 312, 412, 512, 612. At least a portion of the support structure 30, 130, 230, 330, 430, 530, 630 is rigid or semi rigid, so as to retain its shape under gravity and to support a predetermined amount of comestible crustacean material without collapsing under the weight of the same. The support structure 30, 130, 230, 330, 430, 530, 630 defines at least a portion of a platform 32, 132, 232, 332, 432, 532, 632 at an upper end 34, 134, 234, 334, 434, 534, 634 thereof. The platform 32, 132, 232, 332, 432, 532, 632 is located above the reservoir 18, 118, 218, 318, 418, 518, 618 (i.e., at a height above the height of the reservoir, whether or not the comestible crustacean material is at a location axially aligned with the reservoir directly below). In some embodiments, the platform is itself a surface at the upper end of the support structure. In other embodiments, the platform comprises the aforementioned surface as well as a cover, layer or membrane placed thereon. The optional cover, as a component of a platform according to some embodiments, is further discussed below.
In any case, the support structure 30, 130, 230, 330, 430, 530, 630 and platform 32, 132, 232, 332, 432, 532, 632 are configured to support comestible crustacean material 16 placed thereon. For example, the support structure 30, 130, 230, 330, 430, 530, 630 may be configured to hold up to 5 pounds (2.27 kg), optionally up to 10 pounds (4.54 kg), optionally up to 15 pounds (6.80 kg), optionally up to 20 pounds (9.07 kg) of comestible crustacean material over a period of at least two weeks, without collapsing under the weight of the same. Ultimately, the support structure 30, 130, 230, 330, 430, 530, 630 and the platform 32, 132, 232, 332, 432, 532, 632 are configured to suspend comestible crustacean material 16 above the reservoir 18, 118, 218, 318, 418, 518, 618 so as to separate the comestible crustacean material 16 from its exuded juices, which may, via gravity, be directed into the reservoir 18, 118, 218, 318, 418, 518, 618.
The platform 32, 132, 232, 332, 432, 532, 632 and/or support structure 30, 130, 230, 330, 430, 530, 630 are configured to direct liquid exuded from the comestible crustacean material 16 to the reservoir 18, 118, 218, 318, 418, 518, 618. This may be achieved in a variety of ways, exemplary implementations of which are elaborated upon below.
Optionally, the storage container 10, 110, 210, 310, 410, 510, 610 includes a lid 36, 136, 236, 336, 436, 536, 636 to enclose the comestible crustacean material 16 within the storage container 10, 110, 210, 310, 410, 510, 610. In some optional embodiments (not shown), the lid may include a rigid or semi-rigid removable and replaceable closure means, e.g., a snap on lid. Preferably, the lid 36, 136, 236, 336, 436, 636 comprises a flexible lidding film 38, 138, 238, 338, 438, 638. Examples of a lid 36, 136, 236, 336, 436, 636 comprising a flexible lidding film 38, 138, 238, 338, 438, 638 are shown covering and enclosing internal compartments 12, 112, 212, 312, 412, 612 of exemplary embodiments of storage containers 10, 110, 210, 310, 410, 610. As shown in the figures, the lidding film 38, 138, 238, 338, 438, 638 is depicted as having an exaggerated thickness, just so that it is more clearly visible in the figures. In reality, the film's thickness would preferably be less than depicted. For example, the film may be from 0.001 inches to 0.003 inches thick. The lidding film 38, 138, 238, 338, 438, 638 is also preferably attached to the peripheral edge 26, 126, 226, 326, 426, 626 in a taut manner and is thus planar when covering the container opening 28, 128, 228, 328, 428, 628. A headspace is formed within a volume of the product containing space 14, 114, 214, 314, 414, 514, 614, beneath the lid 36, 136, 236, 336, 436, 536, 636, which is not occupied by the comestible crustacean material 16. With a headspace present, neither the lid nor any other covering is tightly wrapped around the comestible crustacean material. If the lid or another covering were wrapped in such a way, it would completely eliminate the presence of a headspace.
Optionally, the lidding film 38, 138, 238, 338, 438, 638 is secured to the peripheral edge 26, 126, 226, 326, 426, 626 of the side wall 24, 124, 224, 324, 424, 624 of the storage container 10, 110, 210, 310, 410, 610, e.g., by a tie layer. Optionally, the tie layer is a polyethylene tie layer that is optionally co-extruded onto the peripheral edge 26, 126, 226, 326, 426, 626, to bond the lidding film 38, 138, 238, 338, 438, 638 thereto by a heat seal 40, 140, 240, 340, 440, 640. Optionally, in these embodiments, the peripheral edge 26, 126, 226, 326, 426, 626 is positioned at the same height along its entire periphery, thus defining a single plane. The lidding film 38, 138, 238, 338, 438, 638 or optionally more generally a lid, when disposed atop the peripheral edge, also optionally occupies a single plane.
Alternatively, as shown in
Regardless of the form of the lid, it is important that the lid provide a desirable oxygen transmission rate for crustaceans. Packaging that provides an oxygen transmission rate of 10,000 cc/m2/24 hrs at 24° C., or higher, is regarded as an oxygen-permeable packaging material for seafood products. An oxygen permeable package should provide sufficient exchange of oxygen to allow naturally occurring, aerobic spoilage organisms on the seafood product to grow and spoil the product before toxin is produced under moderate abuse temperatures. Thus, in one optional embodiment, a lidding film 38, 138, 238, 338, 438, 638 or wrap 538 is disposed over the product containing space 14, 114, 214, 314, 414, 514, 614 to enclose the comestible crustacean material 16 stored therein so as to provide an oxygen permeable package. Optionally, the storage container is enclosed with a lidding film that provides an oxygen transmission rate of at least 10,000 cc/m2/24 hrs at standard temperature and pressure (ASTM D3985). Such film is known in the field as a 10K OTR lidding film. Some products benefit from a much lower oxygen transmission rate. For example, in an optional embodiment, a lidding film providing less than 100 cc/m2/24 hrs may be used. Optionally, the lidding film is transparent, which allows a user to view the quality of the seafood stored in the storage container. Preferably, the lidding film is a polyethylene composition, optionally a biaxially stretched polyethylene composition. For example, the lidding film may be the PLASTOFRESH 10K by PLASTOPIL or the 10K OTR Vacuum Skin Package film by CRYOVAC®.
The storage method of the disclosed concept allows storage of comestible crustacean material in an aerobic environment. The oxygen-permeable lid enables sufficiently high oxygen exchange between the environment inside the container and the environment surrounding the container. Typically, the environment inside the container of the disclosed concept is indistinguishable from the ambient environment outside the container with respect to oxygen content under all relevant storage conditions. In one embodiment, the invented storage method uses a single layer of lidding film for the oxygen-permeable lid. No modified atmosphere packaging methods are necessary in an optional aspect of the disclosed concept. Further, the disclosed concept does not require that the comestible materials be stored under vacuum within the container. Rather, the container allows for oxygen exchange and air exchange into and out of the container. As such, in any embodiment, the product containing space when enclosed by a lid preferably has the same pressure as atmospheric pressure of the ambient environment surrounding the container.
In some optional embodiments (see, e.g.,
In an optional aspect of the disclosed concept, a filled and closed package 11, 111, 211, 311, 411, 511, 611 is provided, comprising the assembled storage container 10, 110, 210, 310, 410, 510, 610 with comestible crustacean material 16 stored therein and with the lid 36, 136, 236, 336, 436, 536, 636 enclosing the comestible crustacean material 16 within the storage container 10, 110, 210, 310, 410, 510, 610.
Elements common to two or more storage container embodiments were described simultaneously above, for brevity. At this point in the disclosure, specific details and features relating to each of the exemplary storage containers will be elaborated upon or, as the case may be, introduced. It should be understood that description of any of the basic or common aspects shared by two or more embodiments will not necessarily be repeated here, since they have already been described above. The following details of the above-described embodiments serve to supplement the disclosure of the various storage containers 10, 110, 210, 310, 410, 610 set forth above.
Alternatively (not shown), a storage container is provided which includes a plurality of individual product containing spaces for storing comestible crustacean material. Aside from the fact that this alternative storage container is divided into separate product containing spaces, any of the disclosed concepts discussed herein may be utilized to carry out this alternative embodiment. Each individual product containing space may include a lidding film enclosing the crustacean material in the given space. In this way, if a lidding film is removed from one product containing space, the other compartments remain sealed so that the unused comestible crustacean material stored in them may be put away again for refrigerated storage, for example.
As discussed above with respect to embodiments of a liquid permeable cover 50, 150, 550, 650, the cover (and platform of which it is a part or of which it forms) provides a liquid permeable surface. Such surface is configured to direct liquid exuded from the comestible crustacean material into the reservoir. The cover may be made from any liquid permeable material that has sufficient durability to withstand wet conditions for at least a couple weeks.
Optionally, in any embodiment, the cover comprises a spunbond synthetic nonwoven material. If a spunbond synthetic nonwoven material is used for the cover, a preferred brand is the AHLSTROM WL257680. Preferably, the material is food contact safe and is compliant with U.S. Federal Food and Drug Administration regulations 21 C.F.R. §§ 177.1630 and 177.1520.
Optionally, in any embodiment, the cover material facilitates unidirectional movement of liquid therethrough, such that the liquid permeates downward from the product containing space into the reservoir, but not vice versa. In other words, the cover material is optionally a one way material. Optionally, such one way material may include TREDEGAR brand plastic films.
Optionally, in any embodiment, the cover is from 50 microns to 500 microns thick, optionally, 250 microns (48 GSM) or 130 microns (20 GSM).
Optionally, in any embodiment, the cover has a porosity of from 200 L/min/m2 to 2,000 L/min/m2, optionally 620 L/min/m2.
Optionally, where the cover lays atop a support structure (e.g., ribs, 46, 48), the cover (e.g., 50) is heat sealed to the upper end (e.g., 34) thereof.
Optionally, cover materials other than nonwovens may include a scrim, for example.
Optionally, in some embodiments, it may be desirable to make the cover stiff. In the case of nonwovens, this may be done using a stiffening finish. Alternatively (or in addition), the rigidity of the material may be provided by increasing its thickness and molding or pleating it into a desired shape. The final material would be rigid or semi rigid. For example, the nonwoven material may be configured to have a mass per unit area of 20 g/m2 to 100 g/m2. Optionally, such material is molded or pleated. Alternatively, such material may be fabricated on a mat that produces the desired shape when a vacuum is applied or forced air is provided through the mat.
Optionally, in any embodiment, the cover has antimicrobial properties. This may be achieved by treating the nonwoven with an antimicrobial finish, comprising, e.g., silver ions or nanoparticles of chlorine dioxide, for example. Alternatively, the antimicrobial elements can be engrained in the material of the nonwoven itself.
It is preferred, although still optional, that an absorbent material 20 is provided within the reservoir 18, 118, 218, 318, 418, 518, 618. As discussed below, the absorbent material 20 may be a composition of matter (e.g., powder mixture) or a single article (e.g., sponge), for example.
Absorbent materials usable in conjunction with methods according to the disclosed concepts include food safe absorbent materials having an absorbent composition of matter suitable for use with food products. The absorbent composition of matter has an absorbency, the absorbency being defined by weight of liquid absorbed/weight of the absorbent composition of matter.
The absorbent material is not particularly limited to any material class. However, the absorbent material needs to be food safe, possesses a desirable absorbency, and exhibits a minimum syneresis. For example, the absorbent material may include one or more of the following: tissue paper, cotton, sponge, fluff pulp, polysaccharide, polyacrylate, psillium fiber, guar gum, locust bean gum, gellan gum, alginic acid, xyloglucan, pectin, chitosan, poly(DL-lactic acid), poly(DL-lactide-co-glycolide), poly-caprolactone, polyacrylamide copolymer, ethylene maleic anhydride copolymer, cross-linked carboxymethylcellulose, polyvinyl alcohol copolymers, cross-linked polyethylene oxide, starch grafted copolymer of polyacrylonitrile, and a cross-linked or non-cross-linked gel-forming polymer.
In a preferred embodiment, the absorbent material comprises a cross-linked or a non-cross-linked gel-forming polymer. Such gel-forming polymer may be water soluble or insoluble. In another preferred embodiment, the absorbent material further comprises at least one of the following: 1) at least one mineral composition, 2) at least one soluble salt having at least one trivalent cation, and 3) an inorganic buffer.
In an optional embodiment, the absorbent material includes at least one non-crosslinked gel-forming water soluble polymer having a first absorbency, the first absorbency being defined by weight of liquid absorbed/weight of the at least one non-crosslinked gel forming polymer, the at least one non-crosslinked gel forming polymer being food safe, the absorbent composition of matter being compatible with food products such that the absorbent composition of matter is food safe when in direct contact with the food products.
In an optional embodiment, the absorbent material includes the following: (i) at least one non-crosslinked gel-forming water soluble polymer having a first absorbency, the first absorbency being defined by weight of liquid absorbed/weight of the at least one non-crosslinked gel forming polymer, the at least one non-crosslinked gel forming polymer being food safe; and (ii) at least one mineral composition having a second absorbency, the second absorbency being defined by weight of liquid absorbed/weight of the at least one mineral composition, the at least one mineral composition being food safe, the absorbency of the absorbent material exceeding the first absorbency and the second absorbency, the absorbent material being compatible with food products such that the absorbent composition of matter is food safe when in direct contact with the food products. It should, however, be understood that alternative absorbent materials such as those described above may be used in accordance with the disclosed concept.
In an optional embodiment, the absorbent material includes the following: (i) at least one non-crosslinked gel-forming water soluble polymer having a first absorbency, the first absorbency being defined by weight of liquid absorbed/weight of the at least one non-crosslinked gel forming polymer, the at least one non-crosslinked gel forming polymer being food safe; and (ii) at least one soluble salt having at least one trivalent cation, the at least one soluble salt having at least one trivalent cation being food safe, the absorbency of the absorbent material exceeding the first absorbency and the second absorbency, the absorbent material being compatible with food products such that the absorbent composition of matter is food safe when in direct contact with the food products. It should, however, be understood that alternative absorbent materials such as those described above may be used in accordance with the disclosed concept.
In an optional embodiment, the absorbent material includes the following: (i) at least one non-crosslinked gel-forming water soluble polymer having a first absorbency, the first absorbency being defined by weight of liquid absorbed/weight of the at least one non-crosslinked gel forming polymer, the at least one non-crosslinked gel forming polymer being food safe; (ii) at least one mineral composition having a second absorbency, the second absorbency being defined by weight of liquid absorbed/weight of the at least one mineral composition, the at least one mineral composition being food safe; and (iii) at least one soluble salt having at least one trivalent cation, the at least one soluble salt having at least one trivalent cation being food safe, the absorbency of the absorbent composition of matter exceeding a sum of the first absorbency and the second absorbency, the absorbent material being compatible with food products such that the absorbent composition of matter is food safe when in direct contact with the food products. It should, however, be understood that alternative absorbent materials such as those described above may be used in accordance with the disclosed concept. Any of the embodiments of the absorbent composition of matter described above may optionally comprise an inorganic or organic buffer.
Optionally, the absorbent material contains from about 10 to 90% by weight, preferably from about 50 to about 80% by weight, and most preferably from about 70 to 75% by weight polymer. The non-crosslinked gel forming polymer can be a cellulose derivative such as carboxymethylcellulose (CMC) and salts thereof, hydroxyethylcellulose, methylcellulose, hydroxypropylmethylcellulose, gelatinized starches, gelatin, dextrose, and other similar components, and may be a mixture of the above. Certain types and grades of CMC are approved for use with food items and are preferred when the absorbent is to be so used. The preferred polymer is a CMC, most preferably sodium salt of CMC having a degree of substitution of about 0.7 to 0.9. The degree of substitution refers to the proportion of hydroxyl groups in the cellulose molecule that have their hydrogen substituted by a carboxymethyl group. The viscosity of a 1% solution of CMC at 25° C., read on a Brookfield viscometer, should be in the range of about 2500 to 12,000 mPa. The CMC used in the Examples following was obtained from Hercules, Inc. of Wilmington, Del. (under the trade name B315) or from AKZO Nobel of Stratford, Conn. (under the trade name AF3085).
The clay ingredient can be any of a variety of materials and is preferably attapulgite, montmorillonite (including bentonite clays such as hectorite), sericite, kaolin, diatomaceous earth, silica, and other similar materials, and mixtures thereof. Preferably, bentonite is used. Bentonite is a type of montmorillonite and is principally a colloidal hydrated aluminum silicate and contains varying quantities of iron, alkali, and alkaline earths. The preferred type of bentonite is hectorite which is mined from specific areas, principally in Nevada. Bentonite used in the Examples following was obtained from American Colloid Company of Arlington Heights, Ill. under the tradename BENTONITE AE-H.
Diatomaceous earth is formed from the fossilized remains of diatoms, which are structured somewhat like honeycomb or sponge. Diatomaceous earth absorbs fluids without swelling by accumulating the fluids in the interstices of the structure. Diatomaceous earth was obtained from American Colloid Company.
The clay and diatomaceous earth are present in an amount from about 10-90% by weight, preferably about 20-30% by weight, however, some applications, such as when the absorbent material is to be used to absorb solutions having a high alkalinity, i.e. marinades for poultry, can incorporate up to about 50% diatomaceous earth. The diatomaceous earth can replace nearly all of the clay, with up to about 2% by weight remaining clay.
The trivalent cation is preferably provided in a soluble salt such as derived from aluminum sulfate, potassium aluminum sulfate, and other soluble salts of metal ions such as aluminum, chromium, and the like. Preferably, the trivalent cation is present at about 1 to 20%, most preferably at about 1 to 8%.
The inorganic buffer is one such as sodium carbonate (soda ash), sodium hexametaphosphate, sodium tripolyphosphate, and other similar materials. The organic buffer may be citric acid, monopotassium phosphate, or buffer mixture with a set pH range. If a buffer is used, it is present preferably at about 0.6%, however beneficial results have been achieved with amounts up to about 15% by weight.
The mixture of the non-crosslinked gel forming polymer, trivalent cation, and clay forms an absorbent material which when hydrated has an improved gel strength over the non-crosslinked gel forming polymer alone. Further, the gel exhibits minimal syneresis, which is exudation of the liquid component of a gel.
In addition, the combined ingredients form an absorbent material which has an absorbent capacity which exceeds the total absorbent capacity of the ingredients individually. While not limited by this theory, it appears that the trivalent cation provides a cross-linking effect on the CMC once in solution, and that the clay swells to absorb and stabilize the gels. Further, as shown by Example D of Table 1 below, it appears that, in some cases at least, it is not necessary to add trivalent cation. It is thought that perhaps a sufficient amount of trivalent cation is present in the bentonite and diatomaceous earth to provide the crosslinking effect.
The gels formed by the absorbent material of the invention are glass clear, firm gels which may have applications in other areas such as for cosmetic materials. Some embodiments of the disclosed concept are set forth in Table 1. As used in Table 1, absorption is defined as the increased weight achieved in an absorbent pad structure of the type described herein, following placement of such pad in a tray-type container with 0.2% saline therein in such quantities as to not limit the access of fluid to the pad for up to 72-96 hours until no further increase of weight is apparent. The net absorption is the difference between the final weight of the pad and the dry starting weight, after deducting the net absorbency of the base pad material other than the absorbent blend i.e. the fabric component. This is converted to a gram/gram number by dividing the net absorption by the total weight of absorbent blend incorporated in the pad. Such a procedure is accurate for comparative purposes when the pad structure used is the same for all the tested blends.
It is apparent from Table 1 that a significant synergistic effect has been achieved in the absorption behavior of these blends, resulting in dramatic improvement in absorption capacity of the blends compared to the individual components. As the non-CMC ingredients are of much lower cost than CMC itself, the blends achieve major reductions in cost per unit weight of absorption.
In the Examples described below, the absorbent material comprises by weight 80-90% carboxymethylcellulose, 5-10% bentonite, 1-5% potassium aluminum sulfate, and 0-10% citric acid. In an optional embodiment, the absorbent material comprises by weight about 87% carboxymethylcellulose, about 10% bentonite, and about 3% potassium aluminum sulfate. In another optional embodiment, the absorbent material comprises by weight about 80% carboxymethylcellulose, about 8% bentonite, about 3% potassium aluminum sulfate, and about 9% citric acid.
The ingredients for the composition are optionally mixed together and then formed into granules. It has been found that preferred embodiments of the invention may be agglomerated by processing without addition of chemicals in a compactor or disk type granulator or similar device to produce granules of uniform and controllable particle size. Granules so formed act as an absorbent with increased rate and capacity of absorption due to the increased surface area of the absorbent. The preferred granule size is from about 75 to 1,000 microns, more preferably from about 150 to 800 microns, and most preferably from about 250 to 600 microns, with the optimum size depending upon the application. Water or another binding agent may be applied to the blend while it is being agitated in the compactor or disk type granulator which may improve the uniformity of particle size. Further, this method is a way in which other ingredients can be included in the composition, such as surfactants, deodorants and antimicrobial agents.
Optionally, one or more odor absorbers may be included in the absorbent material. Examples of such odor absorbers include: zinc chloride optionally in an amount of from greater than 0.0 to 20.0% by weight, zinc oxide optionally in an amount of from greater than 0.0 to 20.0% by weight and citric acid optionally in an amount of from greater than 0.0 to 50.0% by weight. Where the absorbent material comprises from 30% to 80% non-crosslinked gel-forming polymer, optionally carboxymethylcellulose, the amount of the absorbent material is adjusted according to the amount of odor absorber included in the absorbent material.
Optionally, at least one antimicrobial agent is included or blended with the absorbent material. For example, the at least one antimicrobial agent includes compositions described in U.S. Pat. No. 7,863,350, incorporated by reference herein in its entirety. The term “antimicrobial agent” is defined herein as any compound that inhibits or prevents the growth of microbes within the storage container. The term “microbe” is defined herein as a bacterium, fungus, or virus. The antimicrobial agents useful herein include volatile antimicrobial agents and non-volatile antimicrobial agents. Combinations of the volatile and non-volatile antimicrobial agents are also contemplated.
The term “volatile antimicrobial agent” includes any compound that when it comes into contact with a fluid (e.g., liquid exuded from a food product), produces a vapor of antimicrobial agent. In one aspect, the volatile antimicrobial agent is from 0.25 to 20%, 0.25 to 10%, or 0.25 to 5% by weight of the absorbent material. Examples of volatile antimicrobial agents include, but are not limited to, origanum, basil, cinnamaldehyde, chlorine dioxide, vanillin, cilantro oil, clove oil, horseradish oil, mint oil, rosemary, sage, thyme, wasabi or an extract thereof, a bamboo extract, an extract from grapefruit seed, an extract of Rheum palmatum, an extract of Coptis chinesis, lavender oil, lemon oil, eucalyptus oil, peppermint oil, Cananga odorata, Cupressus sempervirens, Curcuma longa, Cymbopogon citratus, Eucalyptus globulus, Pinus radiate, Piper crassinervium, Psidium guayava, Rosmarinus officinalis, Zingiber officinale, thyme, thymol, allyl isothiocyanate (AIT), hinokitiol, carvacrol, eugenol, α-terpinol, sesame oil, or any combination thereof.
Depending upon the application, the volatile antimicrobial agent can be used alone or in combination with solvents or other components. In general, the release of the volatile antimicrobial agent can be varied by the presence of these solvents or components. For example, one or more food safe solvents such as ethanol or sulfur dioxide can be mixed with the volatile antimicrobial agent prior to admixing with the absorbent composition. Alternatively, the volatile antimicrobial agent can be coated with one or more water-soluble materials. Examples of such water-soluble material include cyclodextrin, maltodextrin, corn syrup solid, gum arabic, starch, or any combination thereof. The materials and techniques disclosed in U.S. Published Application No. 2006/0188464 can be used herein to produce the coated volatile antimicrobial agents.
In other aspects, non-volatile antimicrobial agents may be used in combination with or as an alternative to volatile antimicrobial agents. The term “non-volatile antimicrobial agent” includes any compound that when it comes into contact with a fluid (e.g., liquid exuded from a food product), produces minimal to no vapor of antimicrobial agent. In one aspect, the volatile antimicrobial agent is from 0.5 to 15%, 0.5 to 8%, or 0.5 to 5% by weight of the food preservation composition. Examples of non-volatile antimicrobial agents include, but are not limited to, ascorbic acid, a sorbate salt, sorbic acid, citric acid, a citrate salt, lactic acid, a lactate salt, benzoic acid, a benzoate salt, a bicarbonate salt, a chelating compound, an alum salt, nisin, or any combination thereof. The salts include the sodium, potassium, calcium, or magnesium salts of any of the compounds listed above. Specific examples include calcium sorbate, calcium ascorbate, potassium bisulfite, potassium metabisulfite, potassium sorbate, or sodium sorbate.
Optionally, in any embodiment of the disclosed concept, methods and articles for inhibiting or preventing the growth of microbes and/or for killing microbes in a closed package may be utilized. Such methods and articles are described in PCT/US2017/061389, which is incorporated by reference herein in its entirety.
For example, an entrained polymer film material made from a monolithic material comprising a base polymer (e.g., a thermoplastic polymer, such as a polyolefin), a channeling agent (e.g., polyethylene glycol) and an antimicrobial gas releasing agent, may be provided within the storage container. Preferably, the film is secured to the sidewall above a midpoint or is secured (or part of) the underside of the lid.
Optionally, an antimicrobial releasing agent is disposed within the internal compartment, the antimicrobial releasing agent releasing chlorine dioxide gas into the product containing space by reaction of moisture with the antimicrobial releasing agent. The antimicrobial releasing agent is optionally provided in an amount that releases the chlorine dioxide gas to provide a headspace concentration of from 10 parts per million (PPM) to 35 PPM for a period of 16 hours to 36 hours, optionally from 15 PPM to 30 PPM for a period of 16 hours to 36 hours, optionally from 15 PPM to 30 PPM for a period of about 24 hours. Optionally, the antimicrobial releasing agent is a powdered mixture comprising an alkaline metal chlorite, preferably sodium chlorite. Optionally, the powdered mixture further comprises at least one catalyst, optionally sulfuric acid clay, and at least one humidity trigger, optionally calcium chloride.
As used herein, the term “channeling agent” or “channeling agents” is defined as a material that is immiscible with the base polymer and has an affinity to transport a gas phase substance at a faster rate than the base polymer. Optionally, a channeling agent is capable of forming channels through the entrained polymer when formed by mixing the channeling agent with the base polymer. Channeling agents form channels between the surface of the entrained polymer and its interior to transmit moisture into the film to trigger the antimicrobial gas releasing agent and then to allow for such gas to emit into the storage container.
It has been found that methods according to the disclosed concepts provide a surprisingly long shelf life to the stored fresh crustaceans. For example, as explained below, the Applicant has confirmed that after at least 5 days of refrigerated storage according to the disclosed concept, fresh shrimp were better preserved compared to the standard packaging. Applicant's data demonstrates that the inventive methods can successfully store and preserve fresh crustaceans for at least 5 days, optionally from 5 to 10 days.
The term “shelf life” as used herein with reference to fresh crustaceans is the length of time (measured in days) that the seafood may be stored (from the time it is caught) without becoming unfit for consumption. Shelf life may be measured according to common metrics in the seafood industry, such as through basic sensory perception including appearance, smell and taste of the seafood.
This sensory perception may optionally be evaluated according to the hedonic scale. The hedonic scale measures the perception of human test subjects who observe the quality of a given item (using sight or smell) and who indicate the extent of their like or dislike for the item. The hedonic scale used in the present disclosure is a five-point scale. This scale includes the following characterizations of the odor perception as well as visual perception:
The examples below, in which hedonic test results are presented, used ten human test subjects on average per test. For each such test, tabulated results for the test subjects were averaged to provide the data presented herein.
In addition, or alternatively, shelf life may be measured according to propagation of undesirable levels of microorganisms, such as bacteria or yeast and mold, as measured using conventional techniques. The typical storage conditions are conducive to the growth of aerobic bacteria and anaerobic lactic acid bacteria (LAB). LAB usually becomes the dominant bacterial group or occur in very high numbers in raw fish. LAB is also relevant in the spoilage of fish products.
In examples of product storage described herein, refrigerated conditions were used. Unless explicitly stated otherwise for a given example, the term “refrigerated conditions” refers to storage in an environment that is 4° C. at normal atmospheric pressure.
Aerobic Plate Count (APC) or Standard Plate Count (SPC) determines the overall microbial population in a sample. The standard test method is an agar pour plate using Plate Count Agar for determination of the total aerobic microorganisms that will grow from a given sample. The test takes at least two days after which results are given in CFU/g or ml (colony forming units per gram or per milliliter). 3M PETRIFILM™ can also be used to obtain APC or SPCs. APC may also be referred to as Total Plate Count (TPC). LAB counts can be determined in a like manner.
The disclosed concept will be illustrated in more detail with reference to the following Examples, but it should be understood that the disclosed concept is not deemed to be limited thereto.
The absorbent material in the Examples below comprises by weight about 87% carboxymethylcellulose, about 10% bentonite, and about 3% potassium aluminum sulfate.
On day 0, bags of wild caught Argentinian raw easy peel shrimp were received. The shrimp were stored in a freezer during shipment. Three bag of each of the shrimp was taken out and stored in a storage container identified as FPT125D (approximately 12.5″×10.5″×2″) generally similar to that shown in
A sample of three shrimp from each container on each of days 1, 2 and 5 were taken. The odor of the shrimp is scored by ten panelists on the hedonic scale. The results are summarized in Table 2 below.
The Argentinian shrimp smelled fresh in the inventive tray even after 5 days. In comparison, the shrimp stored in the control tray started to give off an odor after 2 days and rapidly declined in odor score throughout 5 days.
While the invention has been described in detail and with reference to specific examples thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.
This application is a Continuation-In-Part of International Application No. PCT/US2018/040485, entitled METHODS FOR PACKAGING AND PRESERVING FRESH SEAFOOD, filed on Jun. 29, 2018 which claims priority under 35 U.S.C. § 119(e) from: U.S. Provisional Patent Application No. 62/527,231, entitled METHODS FOR PACKAGING AND PRESERVING FRESH SEAFOOD, filed on Jun. 30, 2017; U.S. Provisional Patent Application No. 62/641,182, entitled FOOD STORAGE CONTAINERS WITHOUT ANY ABSORBENT MATERIAL, filed on Mar. 9, 2018; and U.S. Provisional Patent Application No. 62/670,610, entitled APPARATUS AND METHOD FOR THE PRESERVATION, STORAGE AND/OR SHIPMENT OF LIQUID-EXUDING PRODUCTS, filed on May 11, 2018. This application also claims the benefit of International Application No. PCT/US2017/061389, entitled ANTIMICROBIAL GAS RELEASING AGENTS AND SYSTEMS AND METHODS FOR USING THE SAME, filed on Nov. 13, 2017. The contents of all of the aforesaid applications are incorporated herein by reference in their entireties.
